3 results about "Digital elevation map" patented technology

The application discloses a kind of single frame unmanned plane image pixel positioning method and system based on elevation map, it is related to unmanned plane image processing and geographic positioning technical field, obtain the single frame original image of unmanned plane shooting and the digital elevation map of the shooting area when unmanned plane attitude information, camera internal and external parameters, shooting;According to camera internal parameter, the pixel coordinates of target pixel in original image are converted to camera normalization plane coordinate system, and target pixel back projection point coordinates are obtained after coordinate distortion correction;According to camera external parameter and unmanned plane attitude information, camera-unmanned plane body coordinate system, body-geographic inertial reference coordinate system conversion is carried out, and the normalized ray direction vector corresponding to target pixel is obtained;Based on digital elevation map, construct ground height constraint, by iterative approximation to space point along ray direction, determine the intersection of ray and ground.The application can realize the fast and accurate conversion of single frame unmanned plane image pixel to geographic coordinate.

The application discloses a typhoon condition large-scale weather prediction downscaling method and system for a wind farm, and a micro-scale database is established through a region segmentation-computation-combination mode based on high-resolution digital elevation maps and roughness data, the computation domain is sequentially calculated according to wind directions after being segmented, an upstream model result is used as a boundary condition for a downstream model, and an overlapping domain flow scaling and interpolation method is used, so that the continuity of the boundary after the combination of each sub-computation domain is ensured, and the influence of the partition computation on the accuracy and continuity of the result is effectively controlled. A new regional dynamic downscaling method is designed, the method realizes long-term numerical simulation with a resolution of dozens of meters in a large region, and effectively reduces the minimum computation resource requirement in the prediction process. In addition to the large-scale weather prediction under the typhoon condition, the method can also be applied to wind power prediction of a wind farm group, and the flexibility and application value are improved.